Such rotary filling machines typically comprise a rotary carrousel bearing a tank of filling product and a plurality of filling stations, each filling station comprising a filling spout connected to the tank, a holder system making it possible to hold a container under the filling spout, and metering means for supplying a determined quantity of filling product into each container.
Such machines should be cleaned regularly with a generally liquid cleaning agent, circulated in the machine in place of the filling product, for removing any traces of product, dust or other foreign matters, and/or possible biological or bacteriological contaminants.
In order to limit the consumption of cleaning agent, it has been known to provide cleaning devices that make it possible to recuperate the cleaning agent exiting the filling spouts with a view to recycling it in a closed circuit-fashion.
These cleaning devices may comprise a plurality of mobile collecting members, such as tubes or receivers, each collecting member being vertically movable between a high service position wherein the collecting member comes tightly in contact with a filling spout to recuperate the cleaning agent supplied by said spout, and a low retracted position wherein said tube is spaced apart from said filling spout for allowing the filling of containers. The collecting members are connected to a same annular manifold moveably mounted on a stationary frame for displacing all the collecting members between their two positions by vertical translation.
The collecting members may be press-fitted all together on cylindrical parts of the filling spouts, wiper seals being thus provided to ensure tightness. Such recovery tubes provided with wiper seals and being press-fitted on the spouts, ensure a good tightness, even when the machine comprises a large number of filling spouts, with height differences between the spouts. Nevertheless, their encumbrance may prove to be incompatible with the holder systems of classic containers.
It is also possible to provide collecting members fitted at their upper ends with an O-ring capable of abutting against the external conical surface of the filling spout or against the lower annular edge surrounding the discharge opening of the spout. Such tightness with an O-ring cannot suit a machine provided with a large number of filling spouts, as in practice, the differences in height between the filling spouts will be inevitably higher than the crushing of an O-ring.
According to another type of cleaning device, each filling spout is provided with a stationary collecting member surrounding the discharge opening of the filling spout and which exhibits a passage opening arranged under the discharge opening of the filling spout, as well as an evacuation duct opening into the inner space of the collecting member for evacuating and recycling the cleaning agent. The device thus comprises a sealing member that can be displaced between a retracted position wherein said sealing member is spaced apart from the filling spout to make it possible to fill a container placed under the filling spout, and a service position wherein said sealing member tightly seals the passage opening of the collecting member to carry out cleaning operations.
An upward vertical translation displacement of the sealing members via a joint displacement system, to displace them to their service position, presents the same aforementioned encumbrance problems, as well as the same tightness problems when the spouts are not perfectly aligned in height. Some machines are provided with an individual displacement system for each sealing member, the displacement between the service and retracted positions being accordingly achieved by a rotation around an axis perpendicular to the axis of the filling spout. These individual displacement systems are particularly cumbersome, and such a rotation movement requires an important available space under the filling spout and around it.